1. Field of the Invention
The present invention relates to display devices such as a liquid crystal display device including a liquid crystal display panel, and more particularly, to the brightness adjustment technology in image display.
2. Description of the Background Art
Nowadays, an auto-stereoscopic image display device capable of stereoscopic viewing without special glasses is proposed. For example, Japanese Patent No. 2857429 discloses a 3-dimensional image display device including a barrier generating unit and an image display unit. The barrier generating unit generates parallax barrier stripes through electronic control by a transmissive display element. The image display unit includes a display screen disposed behind a position at which parallax barrier stripes are generated with a predetermined distance therefrom and, in display of a 3-dimensional image, is capable of outputting and displaying on the display screen a multidirectional image containing stripes for the left image and right image alternately arranged correspondingly to the parallax barrier stripes.
In the 3-dimensional image display device as described above, parallax barrier stripes are generated electronically, and the shape (the number, width, and interval of stripes), position (phase), concentration, and the like of the parallax barrier stripes generated can be variably controlled at will. This enables the above-mentioned 3-dimensional image display device to be used as a 2-dimensional image display device, a 3-dimensional image display device, and display methods using them, realizing a compatible image display device and an image display method using the device.
In the two-image display device (3-dimensional image display device) including a parallax barrier, the lateral (horizontal) pixel aperture width is made smaller with a black matrix (light shielding film) compared with an image display device that displays only a single image. This prevents both lights of two images reaching the left and right eyes from existing, allowing an observer to recognize stereoscopic vision with little crosstalk.
Japanese Patent Application Laid-Open No. 04-145416 (1992) discloses a liquid crystal display device including multiple pixels segmented for RGB basic colors, in which the area ratio or distribution ratio of the pixels to be respectively distributed for the basic colors is changed. The liquid crystal display device described above is configured to easily correct the imbalance in display colors.
In the display device that employs the configuration in which the lateral pixel aperture width is narrowed with a black matrix (light shielding film) and that includes a display panel capable of switching between single image display and two-image display for three dimensions, unfortunately, the pixel aperture width is kept narrow also in a case of normal single image display. This results in a lower transmittance of the display panel than that of an image display device that displays only a single image, which decreases brightness.
In the liquid crystal display device as described in Japanese Patent Application Laid-Open No. 04-145416 (1992), the imbalance in display colors can be corrected by changing the area ratio or distribution ratio of the pixels in the initial design stage of a panel. However, the imbalance in display colors cannot be corrected after manufacturing of the panel and, for example, color adjustment of correcting the imbalance in display colors due to variations in a manufacturing process cannot be performed.